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This study presents a novel development of a new semi-analytical method with diagonal coefficient matrices to model crack issues. Accurate stress intensity factors based on linear elastic fracture mechanics are extracted directly from the semi-analytical method. In this method, only the boundaries of problems are discretized using specific subparametric elements and higher-order Chebyshev mapping functions. Implementing the weighted residual method and using Clenshaw-Curtis numerical integration result in diagonal Euler's differential equations. Consequently, when the local coordinates origin is located at the crack tip, the stress intensity factors can be determined directly without further processing. In order to present infinite stress at the crack tip, a new form of nodal force function is proposed. Validity and accuracy of the proposed method is fully demonstrated through four benchmark problems, which are successfully modeled using a few numbers of degrees of freedom. The numerical results agree very well with the analytical solution, experimental outcomes and the results from existing numerical methods available in the literature. [ABSTRACT FROM AUTHOR]

Objective: an appropriate psychological intervention to promote the level of the public health and mental well-being of nurses has a great importance. This investigation was aimed to study the effectiveness of stress management training on the psychological welfare of nurses in Imam Khomeini Hospital. Methodology: this study was quasi-experimental with pretest-posttest that used a control group. Hence, 40 of the nurses in Imam Khomeini Hospital were selected by using a convenience sampling method and placed in the experimental group and the control group. Both groups were pretested by using psychological well-being 84-question scale. Afterwards, the experimental group was trained for ten sessions under stress management skill exercise, and the check group got no intervention. Next, both societies were post-tested, and the acquired data were analyzed by using inferential and descriptive statistical methods accompanied by SPSS 21 software. Findings: the results indicated that stress management training significantly led to the promotion of psychological well-being in nurses (p < 0.001). Conclusion: it was found from the research that due to the high level of effectiveness of stress management training, its low cost, and its high acceptability by the patients, especially when it was performed in a group, had a significant positive impact on the promotion of psychological well-being in nurses. [ABSTRACT FROM AUTHOR]

There has been some decline in the land potential capacity in many developing countries, and depending on location, the multi objective management strategy of Agroforestry can make effective use of natural resources to be feasible. Environmental principles which are effective on Agroforestry systems and their components, together with climatic factors, are the important parameters which been evaluated in this study. Two cities, Kazeroun (with warm climate) and Sepidan (with cold climate) in Fars province, were chosen for the purpose of this research, and after proper identification and classification of the Agroforestry systems, the effects of climatic factors were analyzed. Nineteen points were identified in these two cities by field investigations, with each type of Agroforestry systems and their corresponding components determined in each point. From the results, most of the systems in Kazeroun, characterized with warm climate, were Agrosilvopastoral, while Sepidan with a characteristic cold climate was the Agrosilvicultural system. Also, the components of each system clearly changed with change in climate, owing to the great importance of the livestock and crop components in Kazeroun and Sepidan, respectively. In general, it can be concluded that the impact of climatic factors on Agroforestry systems and their components has been approved in this study, and the results can be applied in developing these systems in other regions. [ABSTRACT FROM AUTHOR]

Systems where both machines and workers are treated as constraints are termed Dual-Resource Constrained (DRC) systems. In the last few decades, DRC scheduling has attracted much attention from researchers. This paper addresses the Dual- Resource Constrained Flexible Job-Shop Scheduling Problem (DRCFJSP) to minimize makespan. This problem is NP-hard and mainly includes three sub-problems: (1) assigning each operation to a machine out of a set of compatible machines, (2) determining a worker among a set of skilled workers for operating each operation on the selected machine, and (3) sequencing the operations on the machines considering workers in order to optimize the performance measure. This paper presents two meta-heuristic algorithms, namely Simulated Annealing (SA), and Vibration Damping Optimization (VDO), to solve the DRCFJSP. The proposed algorithms make use of various neighborhood structures to search in the solution space. The Taguchi experimental design method as an optimization technique is employed to tune different parameters and operators of the presented algorithms. Numerical experiments with randomly generated test problems are used to evaluate performance of the developed algorithms. A lower bound is used to obtain the minimum value of makespan for the test problems. The computational study confirms the proper quality of the results of the proposed algorithms. [ABSTRACT FROM AUTHOR]